1. Field of the Invention
The present invention relates to medical devices, and particularly to a CSF (cerebrospinal fluid) shunt valve that is self-regulating and responsive to pressure differentials from the fluid being drained or shunted.
2. Description of the Related Art
Obstruction of cerebrospinal fluid (CSF) or its malabsorption leads to intracranial accumulation of CSF resulting in increased intracranial pressure (ICP) or hydrocephalus. This condition requires drainage or shunting of the CSF. As with many medical conditions, the ICP varies in a case-to-case basis, taking into consideration many variables, such as the individual's age, gender, medical history and the like. Generally, the ICP can vary anywhere between 0-20 mm Hg.
Typically, a sterile internal system through a catheter is used to shunt CSF into a body cavity such as the right atrium of the heart, pleural cavity or most commonly, the peritoneal cavity. An essential component to this procedure is a valve situated along the drainage catheter to prevent excessive drainage. Proper shunt selection usually requires accurate ICP measurements and a precision opening pressure valve or a programmable valve. However, the most commonly used valves are valves preset on one of the following differential pressure(s) (DP): low (<7 mmHg), medium (7-11 mmHg), or high (>11 mmHg). While functional, these valves can be subject to complications for the patient when the presumed pressure proves to be inaccurate, leading to improper performance of shunts, such as under- or over-drainage, necessitating replacement of the valve. Moreover, frequent monitoring and changes of the valve may be necessary when accounting for the potential changes in intracranial DP, especially since the pressure can change over time.
In light of the above, it would be a benefit in the medical arts to provide a valve with more universal application that regulates flow dynamically for a wide range of pressures. Thus, a CSF shunt valve solving the aforementioned problems is desired.